﻿using System;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Ink;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
using Slex.Lib.Reactive;

namespace Slex.Lib.Interactions
{
    /// <summary>
    /// A trigger to fire when an event is raised
    /// </summary>
    public class EventTrigger : ObserverTrigger<System.Collections.Generic.Event<EventArgs>>
    {

        /// <summary>
        /// The name of the event to hook to
        /// </summary>
        public string EventName
        {
            get { return (string)GetValue(EventNameProperty); }
            set { SetValue(EventNameProperty, value); }
        }

        // Using a DependencyProperty as the backing store for EventName.  This enables animation, styling, binding, etc...
        public static readonly DependencyProperty EventNameProperty =
            DependencyProperty.Register("EventName", typeof(string), typeof(EventTrigger), new PropertyMetadata(string.Empty));

        

        /// <summary>
        /// Initializes the observable
        /// </summary>
        protected override void Initialize()
        {
            this.Cleanup();

            if (Source == null) 
                throw new InvalidOperationException("Source specified for this trigger is null");
            if (string.IsNullOrEmpty(EventName)) 
                throw new InvalidOperationException("EventName specified for this trigger is null");

            this.Observable = ObservableExtensions.FromEvent(Source, EventName);
        }

        /// <summary>
        /// On next action for this observer trigger
        /// </summary>
        /// <param name="param"></param>
        protected override void OnNext(object param)
        {
            var item=param as System.Collections.Generic.Event<EventArgs>;
            InvokeConditional(new EventResult() 
                { Sender = item.Sender, Args = item.EventArgs });
        }
    }
}
